This invention pertains to the art of structural arrangements for a robot of the type which includes a number of independent arms which converge to a workhead end.
Many conventional industrial robots of which I am aware have a general design arrangement in which a vertical post supports a horizontally extending boom or arm having a workhead at the end of the arm. As such, the arm is subject to a bending moment. To resist bending the structural members of the arm are designed with a relatively high degree of rigidity which makes the arm relatively heavy. Accordingly, the structure supporting the arm is relatively heavier. As an example, a robot arm intended to operate with a payload of, say, 100 pounds (45 kg) will have a structure weighing perhaps over 1000 (454 kg) pounds. Thus the arm may have a weight of ten times the payload. Consequently, the motors for operating the conventional robot are necessarily large and are expensive.
It is the aim of my invention to provide an automatic robot structure that incorporates a concept of best use of the theory of strength of materials in a way that the weight to payload ratio is in the order of one to one. Consequently, operating motor sizes can be significantly smaller. Additionally, other advantages flow from the inventive arrangement with respect to speed and accuracy of operation.